[petsc-users] FE discretization in DMPlex

[Justin Chang]

Hi all,

So I understand how the FEM code works in the DMPlex examples (ex12 and 62). Pardon me if this is a silly question.

1) If I wanted to solve either the poisson or stokes using the discontinuous Galerkin method, is there a way to do this with the built-in DMPlex/FEM functions? Basically each cell/element has its own set of degrees of freedom, and jump/average operations would be needed to "connect" the dofs across element interfaces.

2) Or how about using something like Raviart-Thomas spaces (we'll say lowest order for simplicity). Where the velocity dofs are not nodal quantities, instead they are denoted by edge fluxes (or face fluxes for tetrahedrals). Pressure would be piecewise constant.

Intuitively these should be doable if I were to write my own DMPlex/PetscSection code, but I was wondering if the above two discretizations are achievable in the way ex12 and ex62 are.

Thanks,
Justin